A flexible technique for modifying various chemical substances utilizes a confined path to be followed by these substances in gaseous form or in a gaseous medium. Along this path there is positioned electrically energizeable means for establishing an electric field. Also along the path there are positioned electrically energizeable means for heating the gas to crack certain constituents into free elements; for combusting certain constituents; and for attracting certain constituents through affinity. The electrical energization of these means is controllable to provide the appropriate effect on the substances in the path.
